The present invention relates to a controllable emitter and, more specifically, to a controllable drip line emitter using a solenoid coil and a magnetic stopper.
Current drip irrigation systems are often equipped with pressure compensated emitters that can deliver a certain amount of water to nearby areas based on the fabrication characteristics of the emitters. Typically, the emitters will have a watering rate of 0.5, 1 or 2 gallons per hour delivery. The amount is set in the fabrication process or they can be set manually in the field. This can present problems, however, because industry frequently demands that drip irrigation systems be able to dynamically adjust the amount of water that is delivered to a specific location based on real time information (satellite imagery, field deployed soil moisture sensor, thermal imagery) of the water absorbed/transpired by canopy and water evaporation from soil or soil water retention properties.
Current approaches to the problem of using emitters with a predefined watering rate in a drip irrigation system in which dynamic adjustments are required rely on delivery of the same amount of water in every location where the amount of water is defined as the upper amount required by the most water demanding spot. The inherent differences in soil properties and crop characteristics can thus lead to overwatering in many locations based on such uniform water delivery. Potentially, different rate emitters can be installed in different locations but temporal changes in the irrigation schedule does not permit dynamic adjustments over time.